They were just one block from the hotel where US President George W Bush is staying when the joke was realised.

Morrow says the stunt was not irresponsible and did not endanger anybody.

"I wouldn't think so. Hard to say ... lucky it was us and not Al Qaeda,' he said.

Stupidity

But the former intelligence chief for the Sydney Olympics says The Chaser team put themselves and others at risk.

Security expert Neil Fergus says the stunt was handled well by security forces and the apparent breach is a side issue compared with the stupidity of their act.

"They might have done security a favour, in a bizarre way, because there is no such thing as a perfect security operation," he said.

"The fact that it [the fake motorcade] got through a checkpoint has been taken note of by the competent managers and staff. There'll be some tightening, but again - it's a peripheral issue compared to the stupidity of what those people did."

Mr Fergus says The Chaser team were lucky not to have been hurt.

"If somebody had called out, 'this is a false motorcade' over the communications it is possible something quite serious could have happened," he said.

"So I think the security forces handled it particularly well."

Not amused

Mr Rudd has told Southern Cross Radio he did not find the stunt amusing.

"If you're in Sydney at the moment, the security arrangements are at a very high level and I would very much hate for there to be any injuries, let alone fatalities occurring because people were trying to push the security margins for entertainment purposes," he said.

Possible jail time

The eight cast and crew member and three hire car drivers arrested have been granted conditional bail and will appear in court next month.

New South Wales Police Commissioner Andrew Scipione says those arrested face up to six months in jail.

"I'm angry," he said.

"I'm very angry that this stunt happened. It was a dangerous stunt."

He says he is not thanking The Chaser for exposing the security vulnerability.

"They conducted what was a criminal act and I won't thank anyone for committing crimes," he said.

NSW Premier Morris Iemma says he would have preferred if it did not happen.

"We all enjoy The Chaser program, but what happened was not a joke. The Chaser is not above the law," he said.